1. Field of the Invention
The present invention relates to a linear motor and a method of producing it.
The present invention relates particularly to a linear motor in which one coil is wound around an armature, upper and lower magnetic poles are disposed opposite to each other, and magnetic pole teeth of the upper magnetic pole are disposed alternately with the teeth of the lower magnetic pole, and to a method of producing the linear motor.
2. Description of Related Art
Linear motors having various structures have heretofore been proposed. However, the conventional linear motor structured such that a rotating machine is cut to open and linearly driven is used in many cases.
In the conventional linear motor in which the rotating machine is cut to open and linearly driven, much magnetic flux leaks between an armature and a moving element, a motor thrust is small with respect to an exciting current, and motor efficiency is bad. Furthermore, since a magnetic attraction force acts in one direction between the armature and the moving element, a large burden is applied to a moving element support mechanism, structure is distorted, various troubles occur, and it has been difficult to practically use the linear motor.
An object of the present invention is to provide a linear motor in which a leak magnetic flux flowing between an armature and a moving element is reduced to reduce a one-direction magnetic attraction force generated between the armature and the moving element, and a method of producing the linear motor.
To achieve the object, according to the present invention, there is provided a linear motor provided with an armature including a core formed of a magnetic body and a winding wound around the core, and a moving element supported in such a manner that the moving element can move with respect to the armature via a gap. The linear motor comprises magnetic pole teeth disposed above and below the moving element, disposed at predetermined pitches along a moving direction of the moving element and disposed opposite to each other via the moving element, and a winding for exciting the magnetic pole teeth such that adjacent and opposite magnetic pole teeth have different magnetic poles. The moving element, magnetic pole teeth, and winding constitute the linear motor, and the moving element is reciprocated and moved with respect to the armature by exciting the winding in accordance with a predetermined control circuit.
In other words, the linear motor includes an armature and a moving element capable of moving with respect to the armature. The linear motor further includes one magnetic pole teeth row which is magnetically connected to one magnetic pole of the armature and in which first and second stages of magnetic pole teeth are separated and arranged substantially in a vertical direction to a moving direction of the moving element, and the other magnetic pole teeth row which is magnetically connected to the other magnetic pole of the moving element and in which first and second stages of magnetic pole teeth are separated and arranged substantially in the vertical direction to the moving direction of the moving element. The magnetic pole teeth of the first stage of the magnetic pole teeth row are disposed alternately with the magnetic pole teeth of the first stage of the other magnetic pole teeth row with respect to the moving direction of the moving element. The magnetic pole teeth of the second stage of the magnetic pole teeth row are disposed alternately with the magnetic pole teeth of the second stage of the other magnetic pole teeth row with respect to the moving direction of the moving element. The moving element may be disposed between the magnetic pole teeth of the first stages of the magnetic pole teeth rows and the magnetic pole teeth of the second stages of the magnetic pole teeth rows.